#include<iostream>
#include<string>
#include<cstdio>
#include<vector>
#include<cmath>
#include<algorithm>
#include<functional>
#include<iomanip>
#include<queue>
#include<ciso646>
#include<random>
#include<map>
#include<set>
#include<complex>
#include<bitset>
#include<stack>
#include<unordered_map>
#include<utility>
#include<tuple>
using namespace std;
typedef long long ll;
typedef unsigned int ui;
const ll mod = 1000000007;
const ll INF = (ll)1000000007 * 1000000007;
typedef pair<int, int> P;
#define stop char nyaa;cin>>nyaa;
#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define Rep(i,sta,n) for(int i=sta;i<n;i++)
#define Per(i,sta,n) for(int i=n-1;i>=sta;i--)
#define rep1(i,n) for(int i=1;i<=n;i++)
#define per1(i,n) for(int i=n;i>=1;i--)
#define Rep1(i,sta,n) for(int i=sta;i<=n;i++)
typedef long double ld;
typedef complex<ld> Point;
const ld eps = 1e-8;
const ld pi = acos(-1.0);
typedef pair<ll, ll> LP;

typedef vector< vector< ll > > mat;
typedef vector< ll > vec;
mat mtmul(mat &A, mat &B){
    mat C(A.size(), vec(B[0].size()));
       rep(i, (int)A.size()) {
               rep(k, (int)B.size()) {
                       rep(j, (int)B[0].size()) {
                           C[i][j] = max(C[i][j] , (A[i][k] + B[k][j]) ) ;
                       }
               }
       }
       return C;
}
mat mtpow(mat A, ll n) {
       mat B(A.size(), vec(A.size()));
       rep(i, (int)A.size()) {
            rep(j,(int)A.size()){
                B[i][j]=A[i][j];
            }
       }
       n--;
       while (n > 0) {
               if (n&(ll)1)B = mtmul(B, A);
               A = mtmul(A, A);
               n >>= 1;
       }
       return B;
}

int n,m;
mat A;

void solve(){
    cin >> n >> m;
    A.resize(m,vec(m));
    rep(i,m){
        rep(j,m){
            cin >> A[i][j];
        }
    }
    mat B=mtpow(A,n-1);
    ll ans=0;
    rep(i,m){
        rep(j,m){
            ans=max(B[i][j],ans);
        }
    }
    cout << ans << endl;
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(0);
    cout << fixed << setprecision(50);
    solve();
}